This invention relates to a sealing arrangement for the axially reciprocable piston rod of a Stirling engine.
Stirling engines have received increasing attention in recent years owing to their high torque characteristics, clean exhaust gas, low noise, low fuel expense, low maintenace, and high durability as compared with a conventional gasoline engine. Furthermore, the thermal characteristics of a Stirling engine are equal or superior to those of an internal combustion engine, because in a Stirling engine hydrogen or helium is used as the working fluid instead of air, whereby the temperature characteristics of thermal heat exchangers are greatly improved.
However, since the hydrogen or helium working fluid has relatively small molecules, it is difficult to properly seal a Stirling engine. Stirling engines have exhibited high leakage in the sealing area between the cylinder wall and the piston rod. Conventional "roll-sox" seals are reasonably effective, but their durability and temperature resistance is low due to the materials used therein.